Automatic weighing scale



Filed March 13, 1942 14 Sheets-Sheet l q l l o INVENTOR. BENJAMIN C OOPEI? BY W Jan. 1, 1946. B. COOPER v 2,392,023

AUTOMATIC WEIGHING SCALE Filed March 13, 1942 14 Sheets-Sheet 2 lk I 1.4 l "um". 10

2 E206 C206 mvmok ro. a, BENJAMIN cooPE/Q BY m - 1477'0QNE'Y Jan. 1, 1946. B. COOPER AUTOMATIC WEIGHING SCALE Filed March 13, 1942 14 Sheets-Sheet 3 www mom m INVENTOR. 0 0 PH? Jan. 1, 1946. B. COOPER AUTOMATIC WEIGHING SCALE Filed March 13, 1942 14 Sheets-Sheet 5 INVENTOR. BA-NJAM/N COO/ EA BY {22 r 6 ,47T0/e/v y Jan, 1, 1946. B. COOPER 2,392,023

AUTOMATIC WEIGHING SCALE Filed March 13, 1942 14 Sheets-SheetG D205 205 E206 INVENTOR.

BIF/VJAM/N C OOPE Q A TTOENEY Jan; 1, 1946. a PER 3 2,392,023

AUTOMATIC WEIGHING SCALE Filed March 13, 1942 l4 Sheets-Sheet7 INVENTOR. I BFNJAM/N coo/ 5 9 BY Jan. 1, 1946. a. COOPER AUTOMATIC WEIGHING- SCALE Filed March '13-, 1942' 14 sheets-sheet} INVENTOR. BE/VJ/I M/N, COOPER ATTORNEY.

Jan. 1, 1946. B. COOPER AUTOMATIC WEIGHING SCALE Filed March 13, 1942 14 Sheets-Sheet 9 XNVENTOR. BEA J4 M/N COOPER ATTORNEY.

Jan. 1, 1946. B. COOPER 2,392,023

AUTOMATIC WEIGHING SCALE Fild March 13, 1942 14 Sheets-Sheet 10 aezb 255 illullillll" lllllllilll Illllllll INVENTOR. BENJAM/N COOPER ATTORNEY.

Jan. 1, 1946. B. COOPER AUTOMATIC WEIGHING SCALE l4 Sheets-Sheet ll Filed March 13, 1942 2 R F. P g W W m M m a; 5 c w x3 TV Ai m2 5% H- a mm EN 5 was.

Jan. 1, 1946. B. COOPER AUTOMATIC WEIGHING' SCALE '14 Sheets-Sheet 12 Filed March 13, 1942 i E ,2 b1

Bt'Mf/JM/N COOPER ATTORNEY AUTOMATIC WEIGHING SCALE Filed March 15, 1942 14 Sheets-Sheet 14 INVENTOR. BENJAM/A COOPER ml 221% ATTOQNE'Y Patented Jan. 1, 1946 UNITED STATES PATENT OFFICE 2,392,023 AUTOMATIC WEIGHING SCALE Benjamin Cooper, Netcong, N. J. Application March 13, 1942, Serial No.'434,532

40 Claims.

This invention relates .to automatic weighing scales. It is particularly directed to a scale for automatically weighing, and remotely recording, positive and negative forces applied thereto.

An object of this invention is to provide a scale of the character described, having an automatically traveling noise to balance the load applied to said scale, and electromagnetic means coupled thereto to operate a remote recorder to record the weight of said load as represented by the position of said poise.

A further object of this invention is to provide in a scale of the character described, a multi-unit weight device for automatically increasing or decreasing the capacity of the scale, depending upon the load applied thereto, said multi-unit weight device being operative for a positive or negative capacity of said scale.

AnDther object of this invention is to provide in a scale of the character described, means to control the operation of the unit weight device by the operation of the traveling poise.

A further object of thi invention is to provide in a scale of the character described, means to operatethe unit weight device at different speeds depending upon the loaded condition of said scale.

Still a further object of this invention is to provide in a scale of the character described, means for automatically integrating the weight as represented by the position of the poise and the capacit of the beam as increased or decreased by the operation of the unit weight control, to give the total weight of th load applied thereto, and means for remotely recording the resultant weight.

Still another object of this invention is to provide in a scale of the character described, means to prevent the operation of said scale when the ultimate positive or negative capacity of the scale has been reached.

Yet another object of this invention is to provide in a scale of the character described, means to brake the motor controlling the unit weight devices so that said motor is always returned to a definite zero position after a cycle 01' operation.

Yet a further object of this invention is to provide a highly improved, compact and rugged scale of the character described which shall be easy to operate, and positive in action, which shall have a large variety of applications and yet be practical and efllcient to a high degree in use.

Other objects of this invention will in part be obvious and in part hereinafter pointedout.

The invention accordingly consists in the features of construction, combinations of elements,

and arrangement of parts which will be exemplifled in the construction hereinafter described, and of which th scope of application will be indicated in the following claims.

In the accompanying drawings, in which one of the various possible illustrative embodiments of this invention is shown, 1

Fig. 1 shows a front elevation of an automatic beam scale embodying this invention;

Fig. 2 is a side elevation of Fig. 1;

Fig. 2a is a cross-sectional view taken along line 20-20 of Fig. 2;

Fig. 3 is a cross-sectional view taken along line 3-3 of Fig. l

Fig. 3a is an elevational view with parts broken away, of a bearing support, for the beam of the scale;

Fig. 4 is an enlarged view, partly in front elevation and-partly in vertical section, of the load end of a scale beam embodying the invention;

Fig. 5 is a cross-sectional view taken along line 5-5 of Fig.4;

Fig. 6 is an enlarged view, partly in front elevation and partly in vertical cross-section, of the balancing end of a scale beam and the unit weights cooperating therewith;

Fig. 7 is a view taken along line 1-1 of Fig. 6;

Fig. 8 is a plan view, with a portion broken away, of a unit weight control and differential mechanism;

Fig. 9 is a front elevational view, with a portion broken away. of Fig. 8;

Fig. 10 is a cross-sectional view taken along line i0--l0ofFig.8;

Fig. 11 is a cross-sectional view taken along line'li-l| of Fig. 9;

Fig. is a cross-sectional view showing the details of a friction clutch of Fig. 11;

Fig. 12 is across-sectional view taken along line l2l2 of Fig. 10;

Fig. 12a is a cross-sectional view taken along line lid-Ila of Fig. 12;

Fig. 12!) is a cross-sectional view taken along line i2b-i2b of Fig. 12;

Fig. 13 is a cross-sectional view taken along line l3|3 of Fig. 9;

Fig. 14 is a wiring diagram showing the circuit connections for said scale beam;

. Fig. 15 shows a detailed elevational view of the cams controlling the unit weights;

Fig. 16 comprises two tables. Table A and Table B, showing the increase and decrease, respectively of the scale beam by the action or the unit weights; and

Fig. 17 is a topv plan view of the scale beam.

Referring now in detail to the drawings, 8 designates a scale embodying the invention.

The same comprises a scale cabinet III, the front,

back and a side panel being removed from the cabinet frame, to disclose the interior (Fig. 1). Fixed to the outside of the top wall Illa of said cabinet is a smaller cabinet A. housing automatic and integrating devices as disclosed in Figs. 8 through 13, inclusive. The contents of the cabinet A and operation thereof will be hereinafter described. f 1

Interconnecting the front vertical frame members "lb of cabinet I0, is a horizontal angle shaped member II. Interconnecting the rear vertical frame members IIlc of the cabinet, is another horizontal member II. aligned with the first memb'er'I I. Fixed to both members II, and

spaced apart to form two platform, are two, fiat,

horizontal plates I2 and I3, parallel to the sides of the cabinet. Fastened to plate I2, as by bolts I4, is a yoke shaped member I5, terminating in two vertical upstanding arms I6. Each of the arms I6 is bifurcated at its and forming aligned slots I1. ,Fixed within slots I1, as by pins I8, are bearings I9.

Supported in the bearings I9 is a scale beam 20, having two horizontally aligned, depending knife blades 2I resting in said bearings. Knife blades 2| are beveled at their outer edges to form a point 2Ia with the knife edge thereof. Fixed vertically across each slot I1, of the arms I6, is

a flat plate 22 fixed to said arms by screws 22a. Threaded through a central opening of each plate 22 is a set screw 23 provided with a lock nut 24. The center lines of screws 23 are in a horizontal plane forming a straight-line with the knife edges of the blades 2|. Lateralplay'of the scale beam 20 may be adjusted to a-proper roportion by turning the set screws 23, and locking the same in place by the lock nuts 24. Fixed to the ends of arms I6 and over the slots I1 are cover plates 25 toprotect the bearings I3 and knife blades 2| from dust and grime.

Scale beam 20 comprises a loading end 26, a scale portion 21, and a balancing end 26. Loading end 26 comprises two parallel, vertical, side walls 26, a vertical end wall 30, and a vertical wall 3|, dividing said loading end from the scale portion 21.

1 Threaded in the upper edge of wall 3| is a asoaoas bearing 41 in horizontal alignment with the .bearing 33 in wall 3|. Integral with wall 3|.

and facing the wall 36 are two bosses 36 and 33.

Boss 38 is in horizontal alignment with ledge 31,

and boss 33 being in alignment with a similar boss 40, integral with wall 36. Fixed to boss 33 and ledge 31 is a tare beam 4|, formed with notches 42, and provided witha sliding capacity poise 43. Fixed to bosses 36 and 40 is another tare beam 44, formed with scale markings 44a.

.and' provided with a sliding fractional capacity poise 45. The sliding poises 43 and 46 are provided with thumb screws 46 to fix said poises on said scales to balance the scale in zero position. Journalled in bearing 41 and through bearing 33 is a horizontal, threaded rod 50. Fixed to walls 3| and 36, near the top edges thereof, is a horizontal guide 5|, in perpendicular alignment with the threaded rod 50 (Fig. 3). Fixed to said walls and to the top face of the inverted uoshaped member 35 is a second horizontal guide rod 62 in alignment with guide 5| and rod 60. Threaded on rod is a traveling poise 63, provided with rearwardly extending, insulated arm 63a and with keyways 53b in its upper and lower faces fitting over the guide rods 5| and 62. Arm 63a is adapted to engage the limit switches 48 and 43, to close the same when poise 53 nears the ends of its travel on rod 60. for the purpose hereinafter appearing. The zero or initial position of poise 53 is at'the left hand side of beam 20 (Fig. l) with arm 63a closing switch 46. I

Balancing end 23 comprises two outspread, ex tending arms 64 and 55, integral with the wall 36, and a slightly upwardly extending, damper supporting arm 66, fixed to said wall, and extending beyond the ends of arms 54 and 65. Connected to arm 66 is a damper rod 56a. Fixed into the outer surfaces of arms 54 and 55, and near the outer edges thereof, are two tip knife blades 61, beveled in they same manner as blades 34 and 2|. The

- edges of knife blades 61, 34 and 2| are in the same perpendicular threaded rod 36, the center line of which is in the vertical plane of the edges of knife blades 2|. Threaded on said rod is a stability ball 89, its function and use being old in the art. Threaded in the face of wall 3|, adjacent scale portion 21, is a horizontal, threaded rod 33.

I Threaded on said rod is a sensitivity poise 34 for hereinafter appearing.

The scale portion 21 comprises an inverted U- shaped, horizontal member 36, integral with wall 3|, and terminating in a vertical wall 36 parallel to the wall 3|, formed with a vertical ledge 31 (Fig. 6). 1

Fixed to the member 36, adjacent wall 3|, is a normally open limit switch 48; and adjacent wall 36 is another normally open limit switch 46.

Fixed in the central portion of said wall is a ball.

horizontal plane (Figs. 1 and 1'7).

Fixed to the lower portion of vertical wall 36, is

a depending, angular shaped member I20 having a horizontal arm I2I. (Fig. 1). Fixed to the horizontal plate I3, as by bolts I3a, is an upright support I22 having pivoted thereto a forked lever I23, adapted to engage the horizontal arm I2I to hold the beam 20 against movement. Lever I23 is connected by a lever system I24 to a handle- (not shown) mounted on the front of cabinet I3, whereby said forked lever may be rotated in a counterclockwise direction, to release arm I2I, as shown in Fig. 1. Fixed to support I22 is an adjustable upward stop I25 and an adjustable downward stop I26, adapted to be engaged by arm I2 I to limit the movement of beam 26 upon upsetting the same in the respective directions.

Supported on knife blades 61 is a U-shaped member 63, having upstanding bifurcated arms 63 and a notched horizontal arm 60. Bifurcated arms 63 are formed with notches 6| in which are fixed, as by pins 62, caps 63. Fitted in said caps and resting on the tip knife blades to carry the weight of member 68, are inverted bearings 64. Each bearing 64 has a short stem 64a projecting into opening 63:: no cap as. Fixed to each of the,

arms 66, and across the notch 6|, is a small plate 66, carrying an aligning set screw 61 and a locking nut 66, similar to screw 23 and nut 24'for the lugs 64.

fulcrumknife blades 2|. It wilinow be understood that knife blades 61 engage inverted bear- Supported on the. load knife blades 34 is a loadzontal plates I02 and I03.

is a screw I04, the end of which abuts the contact the notches 12, are small plates 11 bearing align- Fixed to said cap is an ining screws and nuts 18, similar to that used on the fulcrum knife blades 2 I, and for a similar purpose. Fixed to the center point of yoke 10 is a load yard 18, connected to the loading platform of said scale (not shown), or to some other means upon which a weight may act, either as a positive or negative force (up force or down force) .I

Means is provided to rotate the threaded rod 50 to move the traveling poise 53 on said rod to offset the load applied to the beam 20 whenever a weight acts upon the loading yard 19.

To this end, there is provided in the rectangular opening 32, and integral with walls 29 and 90, two horizontal bosses 80. Fixed to the upper surface of said bosses, as by bolts 8I, is an electric motor BM, having a horizontal drive shaft 93. Fixed to the outer end of said shaft is a pinion 84. Fixed to the end of threaded rod 50, and within the rectangular opening 32, is a spur gear 95, to which is aflixed, as by screws 86, a larger spur gear 91, meshing with the pinion 84.

For the purposes hereinafter appearing, there is fixed to the underside of bosses 80, by the bolts 9I, a synchronous transmitter BS, which is part of a synchronous transmitter, receiver set such as sold under the trade name of Selsyn" or Autosyn. Transmitter BS has a horizontal driven Similarly, if contact II8 were moved downwardly a short distance, contacts I I5 and I would close, while contacts H0, I00 and IOI- will close for a greater degree of movement. In all cases, when contact H8 is returned to initial position by the balance of scale beam 20, springs I01, I I8, I I4 and H5 will return their respective contacts to initial condition.

Means is provided to automatically increase or decrease the capacity of scale beam '20 by adding to, or taking away from horizontal bar 80 on said beam unit weights of different values.

shaft 90 with a spur gear 92, meshing with the gear 85. Transmitter BS is driven by motor BM, and performs as a three phase generator.

Referring now to Figures 1 and 2, there is fixed to the side of scale cabinet I0, a vertical'plate 95, formed with a notch 99. Pivoted to said plate, as by pins 91, are two pairs of normally open switch contact arms 98, 99 and I00, IOI. Fixed near the upper and lower edges of plate 95, are two hori- Threaded in plate I02 arm 99; a screw I05, the end of which abuts contact arm 99; and a screw I08 interconnected to contact arm 99 by a coil tension spring I01. Threaded in plate I 03 is a screw IIO, the end of which abuts contact arm I00; a screw III, the end of which abuts contact arm I0 I; and a screw I I2 interconnected by a coil tension spring I I9 to contact arm I00. Contact arms 98 and IN are connected to plate 95 by springs H4 and Ill, respectively.

Fixed to the end of arm 54 of the beam 20, and insulated therefrom by insulation H1, is a contact arm II8 (Fig. 17), extending beyond the end of said arm and through the notch 99 in plate 95 (Fig. 2). Contact arm I I8 is normally midway between the contact arms 99 and I00 when scale beam 20 is in balanced position. By adjustment of screws I05 and II 0, the contacts 99 and I 00- may be adjusted against the tension of springs To this end, there is fixed, inside cabinet I0, to the top wall thereof, as by bolts I16, two parallel. depending plates I11 and I19, spaced apart and made rigid by spacer rods I19, and provided with projecting portions H141 and I19a, respectively (Figs. 2, 6 and '1). Fixed in plate I11, as by screws I11b, is a ball bearing I90. Fixed in plate I18, as by screws I18b, is a second ball bearing I8I, in horizontal alignment with bearing I80. Journaled in bearing I and through bearing I8I is a horizontal shaft I82. Fixed to an end of said shaft, adjacent bearing I8I is a worm gear I81 provided with two insulated studs I81a and I9"). Stud I91a-is placed at a point 25 from the vertical center line of said gear in a counterclockwise direction; while stud I81b is fixed an equal angular distance from said center in a clockwise direction. Fixed to the outer surface of plate I18, in any suitable manner, are normally closed switches UAI and USI. Switch UAI is adapted to beopened upon 155 rotation of gear I81 in a clockwise direction (Fig. 6) by stud I81b, and switch USI is adapted to be opened by a stud I81a upon rotation of gear I81 through an angle of 155 in a counterclockwise direction.

Fixed to the outside surface of plate I19 is a bearing I88 carrying a vertical shaft I84 which extends upwardly through the top of scale cabinet I0. For the purpose hereinafter appearing, there is fixed to said shaft, 'a worm I15 meshing with the worm gear-I81 on shaft I82.

Fixed to said shaft, between plates I11 and I19, is a set of "plus cams I95, comprising cams AI95, BI85, CI95, DI85, and EI95; and a set of minus cams I85, comprising cams AI86, BI88, CI95, DI88, and EI86. Each of said cams is in perpendicular alignment with a notch 80a of bar 80. Each of said cams is formed with one or more notches, as will appear in detail hereinafter.

Fixed in plates I11 and I18, and parallel to shaft I82, is a shaft I89. Independently and rotatably mounted on said shaft, are two similar sets of cam levers I89 and I90, in the planes of cam sets I85 and I86, respectively, and adapted to coact therewith. Levers I88. I are provided I 01 and H8, respectively, so that contact arm with aligned cam followers I9I at adjacent ends,

' adapted to ride over the peripheries of their respective cams. The levers of set I89 have rearwardly extending arms I99, EI89. CI89, DI89 and EI89. Levers I90 have arms AI90, EI90. CI90, DI90 and EI90.

Fixed horizontally'across the projections I11a and H811 of plates I11 and I19, is a vertical guide plate I92, formed with a plurality of grooves I98, each of said grooves being in the vertical plane of one of the levers I99 or I90. Fixed in each of the grooves I99, near the top edge thereof, is a small block I94 provided with a depending stud I95. Slidably received in each of'said grooves, and supported by a corres onding arm AI89, AI90. etc., is a hanger I98. Each of said ha gers comprises two parallel. vertical side walls I91. a

top wall I98, and a wall I99, fixed across said side walls near the lower central portions thereof.

On each wall I99 is a stud 200. perpendicularly aligned with stud I95. It will be understood that each block I94 is within one of the hangers I98. Top walls I98 have threaded therein screws 20I, the lower ends of which abutthe arms of levers. I89 or I90, thus suspending said hangers I96 in the grooves I93. 7

Fitted over studs I94 and 200, and between hangers I96, is a set of "minus" unit weights 205 comprising weights A205, B206, C206, D206 and E206. Each of said unit weights comprises a top hook 201, adapted to be hooked over pins 203, a hook 208, in alignment with a notch 60a and somewhat less than 205 in a clockwise direction.

asoaoas being spaced thereafter at 10 intervals between centerlines of the projections- The last projection t begins at a point 155 and ends at a point from the zero position, to form a notch 12 between said projection t and projection a of 155,"

Cam EI86 is formed with eight notches to form 'eight 5 projections a, b, c, d, e, j, a. h; projection a being spaced in a clockwise direction froma zero position. The projections b, 0, etc. are spaced apart between adjacent projections; projection h beginning at a point 150 and ending at a point somewhat less than 205 from thezero position in a clockwise direction to form a notch o adapted tobe hooked over bar 60, anda weight portion 209 (Fig. 6).

It will be noted that in suspending sets of unit weights 205 and 206 from the pins 203, hangers I96 are pulled downwardly thereby, to rotate sets of levers I89, I90 in a clockwise direction about shaft I88 (Fig. 6), thus holding cam followers I9I against the peripheries of their respective.

cams and sets of cams I85 and I86.

Referring now to Fig. 15, there is disclosed a I detailed view ofthe set of "plus" cams I85 and the set of the "minus cams I86, All of the cams have zero points at the bottom. Cam AI85 is formed with sixteen notches a, b, c, d, e, f. g, 'h, k. m, n, p, q, r. s and t; notch a being 5 in a counterclockwise direction from the zero position, notches b, 0, etc., are thereafter spaced 10 apart, center to center, the notch it being 155 in a counterclockwise direction from said zero position.

Cam BI85 is formed with eight notches a, b, c, d e, f, a and h, each notch being 5 in extent; notch a beginning 10 in a counterclockwise direction from the zero position, notch .b, 0, etc., are thereafter spaced apart 15. between adjacent notches. Notch h of cam BI85 extends from 150 in a counterclockwise direction from the zero position. I

Cam CI 85 isv formed with four 15' notches a, b, c, and d; notch a starting at a point 20 in a counterclockwise direction from the zero P sition and notches b, c, and 11 being thereafter spaced Notch d apart 25 between adjacent notches. begins at a point 140 and ends at a point 155 in a counterclockwise direction from the zero-point.

Cam DI85 is formed with two notches a and bpnotch a beginning at a point in a'counterclockwise direction from the zero position. Notch 5 begins at a point 120 and ends at a point 155 in a counterclockwise direction from the zero P sition. I 'Cam EI85 is formed with a notch a beginning at a point and ending at a point in a'counterciockwise direction from the zero position.

Cam CI86 is formed with four notches to form four 15 projections a, b, c and d. Projection 0 begins at a point 20 from the zero position, while projections b, c and d are spaced thereafter at 25 intervals between adjacent projections. Projection d begins at a point 140 and ends at a point somewhat less than 205 in a clockwise direction from the zero position. Notch v of said cam therefore extends Cam DI88 is formed with two notches to form two projections 41 and 5. Projection a begins at a point 40 and ends at a point 75 in a clockwise direction from the zero position. Projection 5 begins at a' point 120 and ends at a point about 205 in a clockwise direction from the zero position, leaving notch 1: extending a distance of .Cam EI86 is formed with a projection a, beginning at a point 80 and ending at a point somewhat less than 205 ina clockwise direction from p the zero position, and a notch 1: extending for a distance of 235.

It is to be noted that the notches v of the minus" cams I86 all begin at a point somewhat less than 205 from the zero, position in a clockwise direction. Thus, said notches are coextensive with the working portion of the plus cams I85 which extend for 155 in a counterclockwise direction. Similarly, the inoperative portion ofcams.

I85 is coextensive with the working the minus cams I86.

By rotating shaft I82, in the manner to be hereinafter described, the cams I85, and I85 will operate the cam levers I89 and I90, respectively, to add or take off from the horizontal cross bar 60 their respective unit weights 205, 206. By rotating shaft I82 in a clockwise direction, the levers I90 will remain in notches v keeping the minus unit weights 206 on the cross bar 60. Levers I89 portion of will coact with their respective cams to drop the The "minus cam AI is formed with 18 notches to form 16 projections. 11. b, c. e. f. a. h, k, m. n, n. d. r, a and t; the projection 11 being at a point 5 from the zero position in a clockwise direction; and projections b, 0, etc., as

plus" unit weights 205 on bar 60.

.It will be noted thatthe set of unit weights 206 are normally hung on the cross bar 60, and these unit weights balance the beam at zero. In the zero positions of the cams, therefore, the set of weights 206 are imposed upon the beam, whereas, the set of weights 205 are 01! the beam, balancing the beam. When any of the unit weights of the set 205 is hung on the cross bar 60, a plus weight is applied to the beam equivalent to the value of the particular unit weight. When one oi the unit weights 206 is lifted off the cross bar 68, the capacity of the beam is decreased by an equivalent weight. For this reason, the weightsv 208 are minus weights, whereas, the weights 2" are plus weights.

As the shaft I82'is rotated in a clockwise direction, the minus weights remain on the beam,

and the plus weights are selectively applied to the beam, depending upon the extent of the notches in tbevarious cams. As the shaft I82 18 rotated in a counterclockwise direction from zero, the plus unit weights 205 remain off the beam, and the minus unit weights 205 are selectively withdrawn from the beam, depending upon the position and extent of the projections of the cams I05.

Let us assume that the cams 205 and 205 have been rotated through an angle of 15 in a clockwise direction. As cam AI05 reaches the point 5:, follower IOI of lever I09 associated with said cam, will fall into notch a of said cam, causing said lever to be rotated in a clockwise direction about shaft I (Figs. 1 and 6). Arm A189 of said lever will thus be moved downwardl to do posit the unit weight A205 on the cross bar 50 to impose said unit weight on the beam 20 of the scale. As cam AI continues to rotate through an additional 5 angle, follower I9I leaves notch o of said cam, arid its lever I89 is thus rotated in a counterclockwise direction to lift unit weight A205 from bar 50 and withdraw said unit weight from the beam. At the same time, cam B105 has been rotated, permitting the follower IOI of the arm B|00 to fall in notch a of said cam, thus depositing unit weight B205 on' cross bar 50. When shaft I82 has been rotated through an angle of notch b of cam AI8'5 has been reached by follower I5I, to again deposit unit weight A205 on said bar. The notch or of cam Bl85 being 5 in width will permit unit weight B205 to remain on bar 50. Thus, at a point 15 from the zero position, unit weights A205 and B205 have been deposited on bar 50 together with the "minus unit weights 205 which have remained on bar 50.

Assuming that the capacity of beam without the plus and minus unit weights is 250 pounds and designating the value of the unit weights A205,- B205, C205, D205 and E205, for the purpose of illustration, as being 250 pounds, 500 pounds, 1000 pounds, 2000 pounds and 91000 P unds, respectively, table A of Fig. 16 shows the increase of the capacity of beam 20 during the revolution of the plus cams I05 through 155 in a clockwise direction, in which position a total of 8000 pounds may be weighed on the scale (including the 250 pounds on the poise).

Should shaft I02 be rotated in a counterclockwise direction (Fig. 6), the minus" cams I05 are rotated to lift of! their respective minus unit weights 200 from bar 50. In the case of said minus cams the prolections on said cams will rotate levers I00 in a counterclockwise direction (Fig. 6) about shaft I00 to lift the weights 205 from said bar to balance a downward pull on the load yard 15 of the beam. Designating the value of weights A200. B205, C205, D200 and E205, for the purpose of illustration, as being 250 pounds, 500 pounds, 1000 pounds, 2000 pounds and 4000 pounds, respectively, table B of Fig. 16 shows the "minus capacity of beam 20 when shaft I02 is rotated in a counterclockwisedirection for 155, which in the case illustrated, is 7,750 pounds.

It is to be noted that when shaft I02is rotated through an angle of 155 in a clockwise direction from the zero position, all "plus unit weights 205 are on bar 50 and stud I01b on gear I01 will open switch UAI. When shaft I02 is rotated through an angle of 155 in a counterclockw se direction from the zero position, all "minus unit weights have been lifted off the bar 50 and stud I010 opens switch USI.

The unit weight control mechanism cabinet l0, as by bolts 250a, (Figs, 8, 9 and 1,1) is a support 250 formed with a bottom wall 25I, an upright side wall 252, and an upright rear wall 253. Fixed to rear wall 253, and spaced apart therefrom, as by spacer lugs 254, is a vertical wall 25 parallel to wall 253. Bottom wall 251 is formed at one end with a boss 255, and at its central portion with a boss 251. Fixed across the top edges of walls 253 and 255 is a horizontal plate 258 extending slightly beyond the inner face of rear wall 253. Fixed to the rear surface of wall 255 is a bearing 258, (Fig. 13) having an axis parallel to said wall, and aligned with bearing I83 on plate I10 within the scale cabinet l0, and receiving therein the end of the ver'. tical shaft I00 (Fig. '1).

Fixed to boss 255, as by screws 255a, is an electric motor UWM, hereinafter called the unit weight motor, having a horizontal drive shaft 250. Fixed to boss 251, as by screws 251a, is a reduction gear box 25I, having an input shaft 252 coupled with motor shaft 250, and an output shaft 253, at right angles to the input shaft. The end of the output shaft is journalled in a ball bearing 250 in rear wall 253. Fixed on shaft 253, adjacent wall 253, is a gear 203.

Fixed in wall 253, and in perpendicular alignment with bearing 254, is a second ball bearing 255. Fixed in wall 255, and in horizontal alignment with the bearing 255 is a ball bearing 255. Journaled in bearings 255 and 255 is a horizontal shaft 251. For the purpose hereinafter appearing, there is fixed to shaft 251, between the walls 253 and 255, a gear 250, and a larger gear 259.

Referring to Figs. 11 and 11a, there is fixed to the shaft 251 adjacent the front surface of rear wall 253, a sleeve 210 carrying .collar 211 fixed thereto adjacent bearing 255, and an enlarged disc portion 212 likewise fixed thereto and formed with extending lugs 213. Rotatably mounted on sleeve 210, between the portions 21I and 212 thereof, is a clutch gear 210 meshing with the gear 203, and formed with an annular tapering recess 215. Slidably and rotatably mounted on the end of shaft 251 is a clutch cone 215, adapted to fit into and frictionally engage the surfaces of the recess 215. Said cone is formed with through openings 211 receiving lugs 213, and provided with an elongated, threaded hub portion 210. Rotatably mounted about the hub portion 210, and held thereon by a nut 210, is a thrust bearing 200 and a disc 20I provided with two radial pins 202.

when the motor UWM is operated, shaft 250 is rotated through the reduction gear box 25I, rotating the gear 203. Gear 203 thus'rotates clutch gear 210, but as said clutch gear is free to rotate about sleeve 210, shaft 251 will not be rotated.

Means is provided to shift clutch cone 210 into engagement with the surface of recess 215.- To this end, there is fixed to the upper surface of the horizontal plate 250, as by screws 250a, an electromagnet 205, provided with a magnetizing coil 200, a core 205, and a bell crank shaped armature 201, pivoted as at 201a. Armature 201 is formed with an arm 200 provided with an insulated pin 200. For the purpose hereinafter appearing, there is fixed to plate 250, and in- Within cabinet A, and fixed to the top of cale 15 20I by an insulated stud 200. when electromag- Fingers 390, 39| are normally closed, while fingers 332, 393 are normally open. Fingers 390 and 393 are interconnected by an insulated stud 390a. As will hereinafter appear; finger 393 is adapted to be engaged by an insulated stud 393a on armature 281 when electromagnet 283 is energized, to open fingers 380, 39| and close fingers 392, 393. Spring fingers 390, 39| 392 and 393 a are so fixed to plate 238, that pin 393a will engage finger 393 only close to the limitof the counterclockwise rotation of armature 281, when electromagnet 283 is energized and remains energized.

Fixed to the rear wall 233, below plate 238 is a forwardly extending, horizontal shaft 293 (Figs. 8 and 9). Rotatably mounted on said shaft isa sleeve 293a. Fixed to said sleeve, adjacent wall 233 is a lever 293 having arms 291 and 298, the purpose of which will hereinafter be described; and an arm 299 fixed to its outer end. Interconnecting' arm 298 and arm 288 of the armature 281 is a link 298a. Fixed to the end of arm 299 is a square stud pin 300.

Fixed to rear wall 233, and below shaft 293,

are two forwardly extending arms 30|. Journaled in the ends of arms 30| is a horizontal shaft 302 having fixed thereto a depending arm 303 and a bell crank 303, formed with a forwardly extending arm 303 and 9. depending arm 308.

in walls 233 and 233 and in horizontal alignment Arms 303 and 303 are formed at their lower edges with slots 301. Flxedin said slots are,

the blocks 308 having journaled therein the pins 282 of the disc 28L interconnecting the end of arm 303 with an extension 3| 3 on the reduction ear box 23l, is a coil tension spring 3 tending to rotate bell crank 303, and hence shaft 302, in a counterclockwise direction (Fig. 11). Slidably mounted over the square stud 300, and kept thereon by a washer 309, is a yoke shaped link member 3|0, pivoted at its lower end to arm 303 by a pin 3| The eifective length of link member 3|0 may be adjusted by a screw 3| 2 threaded through the top wall thereof and abutting stud 300 (Figs. 9 and 11).

When electromagne't m is energized, .m; m will be moved upwardly, to move link 293a and rotate lever 293 in a counterclockwise direction (Fig. 9). -Sleeve 293a is thus rotated, rotating arm 299 and permitting link member 3|3 to be moved downwardly by the action of spring 3 on arm 303. Bell crank 303 is thus rotated in a counterclockwise direction, rotating therewith shaft 302 and arm 303, causing the blocks 303 and pins 2-82 to move disc 28| to the right (Fig. 11). The clutch cone 213 engages the surface "of annular recess 213. The rotation of shaft 233 is thus transmitted through gears 233 and 213,

" and through the clutch action of cone 213 and gear 213 to the shaft 231. As will be apparent,

the clockwise rotation of hell crank 303 (Fig. 11) will move disc 28| to the left to release the drive of shaft 231.

Referring to Figs. 8. 10 and ast... is Journaled in ;.rear,-'.wall 233, and wall 233; .a hori- :zontal shaft-3|3 having fixed thereon a gear 3 l1,

and a gear 3| B'meshing with the gear 263. F xed tween the walls 233 and 233 is a gear 32| meshing with gear 3" on shaft 3|3. Fixed to shaft 320, adjacent the outer surface ofwall 233, is a spiral gear 322. Fixed to the vertical shaft I83. extending upwardly from scale cabinet I0, is a spiral gear 323 meshing with gear 322.

Thus, the drive of motor UWM is transmitted to shaft I33 to rotate the unit weight cams in the manner heretofore described.

Means is provided to stop the rotation of shaft 320 exactly at an initial zero position upon energization of the electromagnet 235. To this end, there is fixed to a sleeve 323, rotatable on shaft 320, and in alignment with lever 293, a disc 323 formed with a radial notch 323 in its periphery, and an elongated arcuate slot 321. Arm 2980f lever 293 is formed with a depending lug 328 adapted to ride on the periphery of disc 323 and fall into notch 328 of said disc. A coil tension spring 329. interconnecting arm 291-with plate 238, holds said follower in engagement with the periphery of said disc. I The depth to which lug 328 may be dropped into notch 323 may be adjusted by ascrew 32811 on arm 298, and fixed in adjusted position by a lock nut, so that there is some playbetween the sides of the notch and cam I lug to prevent freezing.

Thus, when electromagnet 283 is energized, le-- 323 keeps rotating for at least one revolution.

When lug 328 drops into notch 323 at the end of such revolution, clutch 313, 313 disengages to release the'drive of shaft 231 and hence also the drive of shaft 323. As the gear trains operated by shaft 320 through gears 32| and 322 are rotated at considerable speed. despite the slowing down of motor UWM, as will appear hereinafter, any sudden halt to the rotation of shaft 320 would strip the gears. At the same time, it is very essential that disc 323 is returned to its initial zero position, as will hereinafter become apparent.

Means is therefore provided to gradually decrease the rotation of shaft 320, upon completion of one revolution of disc 323, by permitting said shaft to overrun the disc and then bring it back to an initial zero position. To thisend, there is fixed to shaft 320, between wall 233 and disc 323, an arm 330 formed with a lug 33| passing through the arcuate opening 321 of said disc. Fixed to said ing, as by .a cotter pin '332and collar 333. is

a roller 333. Fixed in the face of disc 323 and on a radial line with notch 353 is a pin 333. Pivoted to disc 323 on diametrically opposite sides of notch 323, as by cotter pin and stud 333, are two, substantially semi-circular, similar, symmetrical, arms 331 and 338 having opposed straight, parallel-faces 338 and 330, respectively. Intercon- 

